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                                                                      EXHIBIT 21


                  LIST OF SUBSIDIARIES AS OF DECEMBER 31, 2001


Williams GP LLC, a Delaware limited liability company, and general partner of
Registrant

Williams Energy Partners L.P., a Delaware limited partnership

Williams OLP, L.P., a Delaware limited partnership

Williams NGL, LLC, a Delaware limited liability company

Williams Terminals Holdings, L.P., a Delaware limited partnership

Williams Pipelines Holdings, L.P., a Delaware limited partnership

Williams Ammonia Pipeline, L.P., a Delaware limited partnership

Williams Fractionation Holdings, L.P., a Delaware limited partnership



